| 摘要 |
<p>A bandgap voltage reference circuit is described in which two sets of bipolar transistors (Q7-Q12, Q13-Q17) are connected so as to accumulate their base-emitter voltages, and currents are caused to flow through the collector-emitter circuits of each transistor (Q7-Q17). The number of transistors in each set, the geometry of each transistor and the currents transmitted through their collector-emitter circuits are selected so that the accumulated base-emitter voltages of the two sets differ by an amount corresponding to a predetermined bandgap voltage, preferably 1.23 volts. The circuitry can be implemented using either CMOS or bipolar fabrication processes, and has a lower error component than prior bandgap references. In the preferred embodiment the first set (Q7-Q12) includes one more transistor than the second set (Q13-Q17), and supports a higher current density than the second set. The bandgap voltage differential between the two transistor sets (Q7-Q12, Q13-Q17) may be reflected back across the inputs to the two sets by means of an operational amplifier circuit (A3,A4) to obtain a ground referenced output voltage which is proportional to the accumulated base-emitter voltage differential between the two transistor sets (Q7-Q12, Q13-Q17).</p> |
